MTC is a blanket term for a series of techniques for data communication and interaction between two machines, and between a machine and a human being through wireless communication techniques and combination of such techniques. There are two meanings associated with Machine to Machine (M2M): the first meaning is a machine, referred to as an intelligent device in the embedded field; the second meaning is a connection between two machines through a network. The MTC is applied extensively in fields such as intelligent measurement, remote monitoring, tracking, medical treatment, etc., facilitating a more intelligentized life style. Compared with traditional communication between two human beings, MTC devices (M2M devices) are enormous in number and apply extensively, with tremendous market prospect.
In MTC communication, long-distance connection techniques mainly include a Global System for Mobile Communications (GSM), a General Packet Radio Service (GPRS), a Universal Mobile Telecommunications System (UMTS) and the like; and short-distance connection techniques mainly include 802.11b/g, Bluetooth, Zigbee, Radio Frequency Identification (RFID) and the like. As the MTC integrates wireless communication and information technology and may be used for bi-directional communication such as remote information collection, parameter setting, and instruction sending, different application solutions, such as safety monitoring, automatic vending, cargo tracking, and the like, may be implemented with the MTC. Almost all devices involved in daily life are likely to become potential service objects. The MTC provides a simple means for establishing a wireless connection among systems, remote devices or with an individual for real-time device data.
GBA refers to a Generic Bootstrapping Architecture, which defines a general mechanism for Key Agreement between a terminal and a server. FIG. 1 illustrates a network model of the GBA, which mainly includes the following network elements:
a User Equipment (UE), which is a blanket term for a terminal (e.g., a mobile phone) and a Universal Subscriber Identity Module (USIM) card/Subscriber Identity Module (SIM) card, wherein the terminal may be a mobile terminal (e.g., a mobile phone, etc.) with a card slot, or a fixed terminal (e.g., a set-top box, etc.) with a card slot;
a Network Application Function (NAF), which is an application server for implementing a business logic function of an application, and providing business service for the terminal after completing authentication of the terminal;
a BSF, i.e., a Bootstrapping Server Function entity, which is a core network element of the GBA; the BSF and the UE implement the authentication through an Authentication and Key Agreement (AKA) protocol, and agree on an application key to be used subsequently for communication between the UE and the NAF; and the BSF can set a life time for the key according to a local strategy;
a Home Subscriber System (HSS), i.e., a home subscriber server, which is used to store authentication data in the USIM/SIM card such as Ki in the SIM card; and
a Subscription Locator Function (SLF), which is a subscription locator function entity, wherein the BSF inquires the SLF for the name of an HSS storing related subscriber data. The SLF is not required in a single-HSS scenario. Nor is the SLF required when the BSF is configured to use a pre-assigned HSS.
A GBA-PUSH, with an architecture as shown in FIG. 2, is a bootstrapping mechanism established on the basis of the GBA, and the GBA-PUSH enables the UE to establish a secure connection with the NAF through a bootstrapping process without being connected to the BSF.
In an MTC system, an MTC server is equivalent to the NAF in the GBA and the GBA-PUSH architecture, and an MTC device is equivalent to the UE in the GBA and the GBA-PUSH architecture. A secure connection between the MTC device and the MTC server may be established through the GBA and the GBA-PUSH architecture.
For many M2M applications, as an MTC subscriber needs to control communication with the MTC device, the MTC device is not allowed to access an MTC server casually. When the MTC server needs to communicate with the MTC device, through a triggering instruction, the MTC server triggers the MTC device to establish a Packet Date Protocol (PDP)/Packet Date Network (PDN) connection. When the MTC device is not connected to an MTC server, an attacker may pretend to be a mobile communication network or an MTC server and send the MTC device a triggering instruction to trigger the MTC device to establish a connection with an MTC server. Therefore, it is required to take a security measure to ensure that the MTC device responds to a triggering instruction that comes from a legitimate mobile communication network or a legitimate MTC server. Currently, in the case that an MTC device is not connected to an MTC server, there is an urgent need for a solution for safe triggering of the MTC device and further establishment of a secure connection between the MTC device and the MTC server.